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  3. The protective function of blood

The protective function of blood

Immunity – immunity of the organism to agents of certain infectious diseases or certain poisons. There are two mechanisms of the immune system: humoral and cellular.

And plural cell immunity

In cellular immunity or cellular protection involves leukocytes and cells of the reticulo-endothelial system.
White blood cells have amoeboid movement, allowing them to capture and digest foreign cells and dead cells of the body. The absorption and digestion of intracellular bacteria, dead cells and alien organism called on phagocytosis. This phenomenon opened Mechnikov.

Main phagocytosis take part in neutrophils, which contain a protein-digesting enzyme, – leykoproteazy et al., As well as substances which destroy bacteria (germicidal) and neutralizing poisons (toxicity control). Neutrophils are called “microphages”. They always leave the capillaries of the mucous membranes of the oral cavity, primarily the gums, nasal cavity, vagina, urethra and other organs and phagocytose bacteria accumulating on their surfaces. Eosinophils contain numerous different enzymes cope with the consequences of immunological reactions. The detected basophils histamine and heparin. Vibrant ability to phagocytosis have monocytes, which are called “macrophages”. An important role in inflammatory processes play a protective lymphocytes accumulate in the inflammatory foci. Also bacteria, white blood cells and the cells of the reticuloendothelial system absorbs also trapped in the body foreign substances (paint, ink, etc.), Digested them, transferred them to the excretory organs or on the surface of the mucous membranes, where discarded.

Phagocytosis increased during fasting, during the summer months, reduced by vitamin deficiency, and in the winter months.
Thus, phagocytosis associated with amoeboid movement ability of leukocytes infiltrate through the capillary walls into the surrounding tissue. This cell protection, or phagocytosis, creates a natural immunity. Furthermore, leukocytes produce antibodies, which also determines both innate and acquired immunity especially. Since phagocytosis provides removal of dead or dying cells of the organism, as demonstrated Mechnikov, phagocytes are involved in the restructuring of the body.
In addition leukocytes contained protease and other enzymes. In all leukocytes other than lymphocytes are oxidizing enzymes – oxidase and lymphocytes – an enzyme that breaks down fat, – the lipase. The humoral immunity is to produce leukocytes and cells of the reticuloendothelial system-specific protective substances of protein nature – antibodies regulated hypothalamic region. Antibodies are produced in lymphocytes. Especially large role in the production of antibodies lymphocytes formed in the thymus and bone marrow.

Foreign proteins, germs, viruses, microbial toxins and other substances that cause the formation of antibodies are called antigens. The antibody, synthesized in the body, is a protein product – gamma-globulin. Antibodies are specific, ie. E. To a specific antigen produced by a specific antibody. Some authors believe that the antibodies are not specific, and there is a single antibody having various actions in response to the introduction of different antigens.
There are the following antibodies, antigens act on:

  • 1) antitoxins – neutralizing, neutralizing poisons, toxins;
  • 2) lysine – dissolving destroying microbes (bactericidin), erythrocytes (hemolysin);
  • 3) pretsipitiny – causing precipitation of protein products formed from the destroyed microbes, or precipitation of protein solutions;
  • 4) opsonins – preparing microbes to digest their phagocytes by sticking to him plasma proteins;
  • 5) agglutinins – gluing germs or foreign erythrocytes.

For protective substances applies properdin protein component contained in the plasma. In humans, the amount is 0.03% of the plasma proteins.
With the penetration of the body’s cells foreign nucleic acids are isolated polypeptide – interferon. It inhibits virus replication, inhibits the genetic information contained in the foreign nucleic acid, and protecting the body from its mutations. Interferon is produced in all cells, but particularly his leukocytes and produce cells of the reticuloendothelial system of the spleen. Increasing the temperature increases, and lowering reduces its isolation. It has species specificity. In healthy people, it is not found.